1. Field
The present disclosure relates to a positive active material, a positive electrode including the positive active material, and a lithium battery including the positive electrode.
2. Description of the Related Art
Due to the advancements of small, high tech devices such as digital cameras, mobile devices, laptops, and computers, demand for lithium secondary batteries as energy sources for such devices is rapidly increasing. Also, due to the commercialization of plug-in vehicles (also known as xEV), that is, hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (PHEV), and electric vehicles (EV), safe lithium ion batteries having high capacity have been developed. To manufacture lithium batteries suitable for this purpose, various positive active materials have been tested.
As a positive active material of a lithium secondary battery, a single lithium cobalt oxide (LiCoO2) has been used. A layered structure lithium composite metal oxide having high capacity (such as Li(Ni—Co—Mn)O2, Li(Ni—Co—Al)O2) has also been used. In addition, a spinel-type lithium manganese oxide (LiMn2O4) and an olivine-type iron phosphate oxide having high stability have drawn attention.
However, there is a still a need for a positive active material capable of conferring high capacity, improved lifespan characteristics, and thermal stability to a lithium battery.